.clearfix::after {
    content: '';
    display: block;
    height: 0;
    line-height: 0;
    clear: both;
    visibility: hidden;
    opacity: 0;
}

@media (min-device-pixel-ratio: 1.5), (-webkit-min-device-pixel-ratio: 1.5) {
    .border-1px::after {
        transform: scaleY(.7);
    }
}

@media (min-device-pixel-ratio: 2), (-webkit-min-device-pixel-ratio: 2) {
    .border-1px::after {
        transform: scaleY(.5);
    }
}